Link URL rewriting when link is same domain

Hello,

I'm using version 2.1 in a simple CMS application and the problem I have is that when I add in links to pages within the same domain (absolute or root relative) the links are rewritten automatically to be relative like so:

http://mydomain.com/portfolio/food-and- ... nt-search/
gets rewritten to:
../portfolio/food-and-drink-guides/online-restaurant-search/

This obviously breaks the links! I found this post: viewtopic.php?f=6&t=8339&p=21815&hilit=+links+same+domain#p21815
but I can't find any of the code it mentions in my version of the FCKeditor.

Can anyone tell me if there is a setting to switch of URL rewriting or a workaround?

Many thanks
Julian